Envelope having tamper detection means



Jan. 4, 1949.

D. L. DRUMMOND ENVELOPE HAVING 'TAMPER DETECTION MEANS Filed Aug.. 25, 1945 v I N V EN TOR Patented Jan. 4, 1949 UN STATES: TEN OEFICE.

2;4573094; V ENveLoPIi mivmc; 'raiur nn i)lirriie'rron .MEANS DonaldL.Drummond' santaMai-ia.Calif. Application Au u tus;- 1945; Si-ial Nb.612.192

This inventionirelates to improvements? in;- ene.

velop'es, and aims; among cotherrthingsg to.::pr0.=.:

vide an envelope which is cheap and simple .to'xf hesive where needed and sold as a flatIsingle-sheet.

for easy assembly by the user; wherein means are provided for -mak-ing detection easy-ur- -the envelope is'tampered with; and wherein, when de sired; specialmeans may be 'provided for causing discoloratiomof parts thereof'inthe eventvthat the envelope is steamed open.

Having thus brieflyand broadlystated some of the objects and advantagesrofyfthe invention *1 will nowtdescribe, it. infdetailrwithvtlre aid'izbt, the accompanying drawing. in wh ch:

Figure 1 is a rear view of the envelope when closed.

Figure 2 shows the envelope fully open but creased for folding.

Figure 3 shows the envelope with the rear panel, the ears and the flap partly folded, and the larger tabs in folded position.

Figure 4 is a rear view of the envelope showing one side of the rear panel bent back somewhat, and

Figure 5 is another rear view showing portions broken away to disclose the relative positions of the tabs and ears.

Figure 6 is a section on the line 6-6 of Figure 1, and

Figure 7 is a detail showing a modified gumming arrangement.

Referring to the drawing, my envelope consists of a single piece of paper or other suitable material folded at 2 to form a front panel 3 and a rear panel a, and extending from the end of the rent panel 3 remo e f om the fold 2 is a'fiap 5 which is rearwardly folded at 6 and is usually provided with adhesive as shown at 5a for attachment across the rear or outer face of the rear panel 4. Formed integral with each lateral margin of the frontv panel 3 are tabs 1 and 8 which are inwardly folded at 9 against the rear face of the said panel. Formed integral with each lateral margin of the rear panel 4 is an ear l which is inwardly folded at H against the front face of the said panel. The folds 9 and II on r each side of the envelope are in alignment, and the folds H are slit at H from the outer extremity of the rear panel 4 for a distance slightly greater than the depth of the tabs 1 along their folds 9. The tabs 7 which extend from adjacent the'flap 5 continue for foldsflithan the tabs 8 centitheitahs; T substantially to the fold 2.. The.

1 and 8 are preferably inclined atowardone "another from'the folds, 9..

opposite sides: of: the tabs The-front faces .ofthe: folded ears 10' are ad he'sivelyl:securedr-to:theirear' faces of the folded tabs'inflmandyuthe tabs 1 v7 are inserted through the slitsrl t andvlieibetween' therear faces of the ears l0 ancl tlie front-oninner faces of the rear 4 to-zboth of; whi-chlthey: areladhesively secured so -that a communication (not shown) of substa-ntiallythe'samewidth and height asthe panels 3 andl4vmay bexinserted directly against the inner face-pf the front panel 3 afterwhich the flap 5 is adhesively secured to the outer face of thearear panel-4 in the conventional manner.

The adhesiveattachments; with the exception of course of the flap 5 to the rear panel 4, may be made either during fabrication or subsequently by the user. In the latter case I prefer that adhesive be applied to the front faces of the tabs 1 as shown at 1a for attachment to the rear faces of the upper portions of the ears Ill, that is the portions of the ears which lie adjacent the outer ends of the rear panel 4; to the rear faces of the larger tabs 8 as shown at 8a. for attachment to the front faces of the ears l0; and to the front face of. the rear panel 4 as shown at 4a opposite the tabs 1 for attachment to the rear faces of the latter. Perforations l4 are also preferably formed in the tabs 1 and 8 and in the flap 5 so that tears are very liable to occur in the envelope, when sealed, is tampered with. To facilitate detection in the event of tampering someof the surfaces, for instance the portion ii? of the rear panel 4 against which the flap 5 is sealed may have a piece of acid or alkaline impregnated paper l5 secured thereon; on the opposite face of the paper l5 a piece of indicator paper it such as neutral litmus paper is adhesively secured, and the outer face of the indicator paper is gummed for sealing against the rear flap 5. Then if the flap 5 is steamed open the impregnated paper l5 discolors the indicator paper [6 as the adhesive between them is broken down and the discoloration is visible through the perforations in the flap.

While in the foregoing the preferred embodiment of the invention has been described and shown, it is understood that alterations and modifications may be made thereto provided the said alterations and modifications fall within the scope of the appended claims.

What I claim is:

1. An envelope including a piece of material panel opposite sides of the rear panel between the latter and the front panel, adhesive means for securing the tabs and ears on each side to one another and both ears to the inner face of the rear panel, at least one of the adhesive means including alayer of impregnated paper adhesively attached to one M portion of the envelope, a piece of indicator paper adhesively attached to the impregnated paper whereby discoloration of the indicator paper may be observed through the perforations, and a layer of adhesive on the outer face of the indicator paper for securing it to another portion of the envelope.

2. An envelope including a piece of material folded upon itself to form a front and a rear panel, a flap extending from the extremity of the front panel remote from said fold, said flap being folded back over the rear panel for attachment thereto, inwardly folded tabs on opposite sides of the front panel, inwardly folded ears on opposite sides of the rear panel, the ears on each side being partly severed from the rear panel by slits extending along the folds, one tab on each side extending through one of the slits and lying between one of the ears and the rear panel and the other tab on each side lying between one ear and the front panel, and adhesive means for securing the tabs on each side of the ear on that side.

3. The combination in claim 2, wherein adhesive means is provided for attachment of one tab on each side to the rear panel.

4. An envelope including a piece of material folded upon itself to form a front and a rear panel, a flap extending from the extremity of the front panel remote from said fold, said flap being folded back for attachment to the rear panel, inwardly folded tabs on opposite sides of the front panel, inwardly folded ears on opposite sides of the rear panel slit along said folds from the outer extremity of the rear panel for a distance slightly greater than the depth of the tabs adjacent the flap, the latter tabs extending through said slits and lying between the rear panel and the ears, the tabs adjacent the folded end of the front panel lying between the latter and the ears, and adhesive means for securing the tabs and ear on each-side to one another, and the tabs extending through the slits to the rear panels.

5. The combination in claim 4, wherein the adhesive means includes layers of gum on the front faces of the tabs adjacent the flap, on the rear facesof the othertabs, and on the inner face of the rear panel opposite the tabs adjacent the flap.

' DONALD L. DRUMMOND.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 880;!936 Thompson Mar. 3, 1908 1,233,780- Hotchkiss July 17, 1917 FOREIGN PATENTS Number Country Date 19,629 Great Britain A. D. 1889 

